A liquid crystal display system mainly consists of a LCD panel and a backlight module. The structure of the current mainstream thin film transistor liquid crystal display (TFT-LCD) mainly comprises: a lower polarizer, an array substrate, a liquid crystal layer, a color filter substrate and an upper polarizer. The thin film transistors (TFT) in the array substrate are used for controlling the twist of the liquid crystal molecules, thereby realizing a function of an optical switch, transmitting or blocking light emitted from the light source of the backlight module. The array substrate comprises a plurality of sub-pixels arranged in an array; the color filter substrate comprises a plurality of color filters corresponding to the sub-pixels, each sub-pixel is independently controlled to realize color display.
The light source used in the backlight module of the traditional liquid crystal display system is a cold cathode fluorescent lamp (CCFL) or a light emitting diode (LED). Applying a CCFL or LED as the light source of the backlight module is a mature technology at present.
However, if CCFL is used as the light source of the backlight module, the color richness is relatively poor; color gamut range is not wide; moreover, it's not environmentally friendly due to the contained mercury. If LED is used as the light source of the backlight module, a large number of LEDs are required since an LED is approximately a point light source, resulting in high power consumption, raising the temperature of the module; if a light guide plate is used, the structure is relatively complex, and the thickness of the whole backlight module is increased.